1. Field of the Invention
The present invention relates to a neutralizer for cold waving. More specifically, it relates to a neutralizer for cold waving which is formulated by incorporating dibenzyl ketone, p-diacetyl benzene, 2-hydroxy-1,4-naphthoquinone, hinokitiol, shikonin, or a similar compound into a conventional neutralizer containing as a main ingredient an oxidizing agent. This neutralizer has the following two characteristics:
(a) An unpleasant odor (e.g., a mercaptan odor) is not substantially generated in the hair when the neutralizer is applied to the hair; and PA1 (b) An elastic and shiny wave is formed in the hair. PA1 --R.sub.6 is a hydrogen atom, or an alkyl or alkenyl group having up to 3 carbon atoms; PA1 --R.sub.7 is --H, --OH, or --CH.sub.3 ; and PA1 --R.sub.8 is --H, --COCH(CH.sub.3).sub.2, --COCH.dbd.C(CH.sub.3).sub.2, --COCH.sub.3,
2. Description of the Prior Art
As is well known in the art, permanent waving lotions are composed of (i) waving lotions containing, as a main component, reducing agents, that is, mercapto compounds such as thioglycolic acid and cysteine, and (ii) neutralizers containing oxidizing agents such as sodium bromate and hydrogen peroxide. However, the use of conventional permanent waving lotions involves a problem in that an extremely unpleasant mercaptan odor is generated in the hair when the permanent waving lotions are applied to the hair. This unpleasant odor specific to the permanent waving lotions cannot be removed from the hair even when the hair is shampooed several times. Thus, the use of conventional permanent waving lotions is not agreeable to consumers.
Various attempts have been made to eliminate the above-mentioned unpleasant mercaptan odor, among which are typical conventional methods for eliminating the unpleasant mercaptan odor employing so-called masking techniques in which perfumes having a strong odor are incorporated into permanent waving lotions, to thereby mask the unpleasant mercaptan odor in the hair.
However, the mercaptan odor still remains in the hair and has a bad or unpleasant odor. Moreover, since the density of gaseous mercaptan is heavier than that of air, the mercaptan odor drifts down from the hair toward the neighborhood of the nose, especially during shampooing or perspiration. Therefore, the mercaptan odor cannot be completely mashed by the perfume odor remaining in the hair. Furthermore, some people dislike the perfumes which are generally used in these masking methods, due to their strong and heavy odor.
For the above-mentioned reasons, it is considered that the mercaptan odor per se must be eliminated in order to fundamentally solve the above-mentioned problems of unpleasant odor.